Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C11/00—Tyre tread bands; Tread patterns; Anti-skid inserts
  • B60C11/03—Tread patterns
  • B60C11/12—Tread patterns characterised by the use of narrow slits or incisions, e.g. sipes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C11/00—Tyre tread bands; Tread patterns; Anti-skid inserts
  • B60C11/03—Tread patterns
  • B60C11/12—Tread patterns characterised by the use of narrow slits or incisions, e.g. sipes
  • B60C11/1204—Tread patterns characterised by the use of narrow slits or incisions, e.g. sipes with special shape of the sipe
  • B60C11/1218—Three-dimensional shape with regard to depth and extending direction
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C11/00—Tyre tread bands; Tread patterns; Anti-skid inserts
  • B60C11/03—Tread patterns
  • B60C11/12—Tread patterns characterised by the use of narrow slits or incisions, e.g. sipes
  • B60C11/1204—Tread patterns characterised by the use of narrow slits or incisions, e.g. sipes with special shape of the sipe
  • B60C2011/1213—Tread patterns characterised by the use of narrow slits or incisions, e.g. sipes with special shape of the sipe sinusoidal or zigzag at the tread surface

Definitions

• the present invention relates to a pneumatic tire, and more particularly, to a pneumatic tire having a block provided with a sipe in a tread.
• a tire 102 for example, Patent Documents 1 and 2
• a block pattern having a sipe 100 extending in the tire axial direction generally has a sipe before and after the block 104 is worn.
• Fig. 8 (B) there is a step in the circumferential direction (so-called heat and toe wear), and the degree of wear is particularly large at the part that opens in the main groove! /,It is known.
• Patent Document 1 JP 2002-321509 A
• Patent Document 2 JP-A-9-164815
• the present invention has been made to solve the above problems, and an object of the present invention is to provide a pneumatic tire capable of achieving both uneven wear and wet and snow performance.
• the invention of claim 1 is a pneumatic tire having a block in a tread, wherein the tread has at least one sipe, and the sipe has a sipe longitudinal direction and a depth direction.
• the pneumatic tire is characterized in that the stiffness index F shown below varies in the longitudinal direction of the sipe.
• Stiffness index F (1 + ⁇ 1) X (1 + ⁇ 2) X (1 + ⁇ 3)
• ⁇ 2 Sipe amplitude (mm) when the block is viewed perpendicularly to the sipe wall and in cross-section in the depth direction
• ⁇ 3 Amplitude of a ridge line extending in the depth direction of the sipe when the wall surface of the sipe is viewed in plan.
• a three-dimensional sipe having amplitude in the sipe longitudinal direction and the depth direction is provided in the block, and the sipe depth is kept constant by setting the amplitude amount to be different in the sipe longitudinal direction.
• the rigidity in the vicinity of the sipe can be distributed in the sipe longitudinal direction as it is, and for example, the wear before and after the sipe can be made uniform along the sipe longitudinal direction.
• the invention according to claim 2 is the pneumatic tire according to claim 1, wherein at least one end of the sipe is open to the block end, and the sipe of the portion that is open to the block end.
• the rigidity index F is set to be higher than the rigidity index of the sipe at the central portion of the block.
• the sipe stiffness index F is set higher on the block end side than the center of the block so as to suppress a decrease in rigidity near the block end.
• the invention according to claim 3 is the pneumatic tire according to claim 1, wherein the sipe pattern of the block arranged on one side with respect to the tire equatorial plane and the sipe pattern arranged on the other side.
• the sipe pattern of the block is symmetrical with respect to the tire equatorial plane, and the rigidity index F of the sipe gradually increases from the tread center side to the tread end side in the block. It is a feature.
• the tread pattern has no directionality, it is not determined by rotation or the like which side of the tread tire equatorial plane is arranged outside the vehicle.
• the rigidity index F of the sipe is gradually increased from the tread center side toward the tread end side, and a large force is applied when a lateral force is input. It is preferable to suppress deformation of the acting block.
• the invention according to claim 4 is the pneumatic tire according to claim 1, wherein the sipe pattern of the block disposed on one side with respect to the tire equator surface and the sipe pattern disposed on the other side.
• the sipe pattern of the block is asymmetrical with respect to the tire equatorial plane, and within the block, the rigidity index F of the sipe gradually increases from the inside when the vehicle is mounted to the outside when the vehicle is mounted. It is characterized by that.
• the block sipe pattern arranged on one side with respect to the tire equator plane and the sipe pattern of the block arranged on the other side sandwich the tire equator plane.
• the tire has a directional pattern, and the tire orientation is specified when the vehicle is installed.
• the invention according to claim 5 is the pneumatic tire according to claim 2, wherein the sipe amplitude ⁇ 1 is larger in a portion opened to the block end than in a block central portion. It is characterized by that.
• the invention according to claim 6 is the pneumatic tire according to claim 2, wherein the sipe amplitude ⁇ 2 is larger in a portion opened to the block end than in the block central portion. It is characterized by that.
• the sipe amplitude ⁇ 2 By setting the sipe amplitude ⁇ 2 to be larger at the part that opens toward the end of the block than at the center part of the block, it is possible to suppress a decrease in the block rigidity near the opening and make the block rigidity uniform in the longitudinal direction of the sipe. It becomes possible to make it. As a result, the heel and toe wear of the opening portion of the main groove can be suppressed.
• the invention according to claim 7 is the pneumatic tire according to claim 2, wherein the sipe amplitude ⁇ 3 is larger in a portion opened to the block end than in a central portion of the block. It is characterized by that.
• the invention according to claim 8 is the pneumatic tire according to any one of claims 1 to 7, wherein one end of the sipe is in a central portion of the block. It is. Next, the operation of the pneumatic tire according to claim 8 will be described.
• the invention according to claim 9 is the pneumatic tire according to any one of claims 1 to 7, wherein the sipes cross the block in the tire axial direction. It is characterized by this.
• the edge effect can be obtained by traversing the sipe in the tire axial direction.
• FIG. 1 is a plan view of a tread of a pneumatic tire according to a first embodiment.
• FIG. 2A is a perspective view of a sipe wall surface.
• FIG. 2B is a sectional view of the main groove opening side of the sipe.
• FIG. 2C is a cross-sectional view of the terminal end side in the block.
• FIG. 2D is a plan view of the block.
• FIG. 2E is a front view of the sipe wall surface.
• FIG. 3 is a plan view of a tread of a pneumatic tire according to a second embodiment.
• FIG. 4A is a perspective view of a sipe wall surface of a pneumatic tire according to a third embodiment.
• FIG. 4B is a sectional view of the main groove opening side of the sipe.
• FIG. 4C is a cross-sectional view of the center portion of the block.
• FIG. 4D is a plan view of the block.
• FIG. 5A is a plan view of a tread of a pneumatic tire according to Comparative Example 1.
• FIG. 5B is a cross-sectional view taken along the line 5B-5B of the block shown in FIG. 5 (A).
• FIG. 6A is a plan view of a tread of a pneumatic tire according to Comparative Example 2.
• FIG. 6B is a cross-sectional view taken along the line 6B-6B of the block shown in FIG. 6 (A).
• FIG. 7A is a plan view of a tread of a pneumatic tire according to an example.
• FIG. 7B is a sectional view taken along line 7B-7B of the block shown in FIG. 7 (A).
• FIG. 8A is a side view of a new tire.
• FIG. 8B is a side view of the tire after wear.
• FIG. 9A is a plan view of a conventional block.
• FIG. 9B is a cross-sectional view taken along line 9B-9B of the block (when new) shown in FIG. 9 (A).
• FIG. 9C is a cross-sectional view of the block after wear.
• the tread 12 of the pneumatic tire 10 of the present embodiment has a circumferential main groove 1.
• the sipe 20 has one end opened to the block end on the outer side in the tire axial direction of the block 18, and the other end is terminated inside the block 18.
• the pneumatic tire 10 of the present embodiment has a pattern that does not have directionality when mounted on the vehicle.
• the sipe 20 extends in a zigzag shape in the tire axial direction (arrow L direction and arrow R direction) and in the depth direction (arrow D direction).
• Sipe longitudinal direction arrow L direction and arrow R direction
• the sipe 20 has a constant depth.
• the sipe 20 is characterized in that the following stiffness index F differs in the sipe longitudinal direction.
• Stiffness index F (1 + ⁇ 1) X (1 + ⁇ 2) X (1 + ⁇ 3)
• ⁇ 1 Sipe amplitude at the tread of the block (mm). See Fig. 2 (A) and (D).
• ⁇ 2 The sipe amplitude (mm) when the block 18 is viewed perpendicularly to the sipe 20 appearing on the tread and in a cross section in the depth direction. See Fig. 2 (B) and (C).
• ⁇ 3 The amplitude of the ridgeline 22 extending in the depth direction of the sipe 20 when the wall surface 20A of the sipe 20 is viewed in plan. See Figure 2 (E).
• the sipe 20 of the present embodiment has a sipe amplitude ⁇ 1 on the outer side in the tire axial direction larger than a sipe amplitude ⁇ 1 ′ on the tire equatorial plane CL side.
• the sipe amplitude ⁇ 2 on the outer side in the tire axial direction is set larger than the sipe amplitude ⁇ 2 ′ on the tire equatorial plane CL side.
• the stiffness index F of the sipe 20 is larger than the tire equatorial plane CL side when the tire axially outer side opened at the block end opens at the block end.
• the sipe 20 having a three-dimensional wall surface 20A is provided on the block 18, the sipe 20 having a planar wall surface is in close contact with each other when receiving a longitudinal compressive force at the time of ground contact. Compared to, the effect of suppressing the collapse of the block 18 is great.
• the block rigidity in the vicinity of the opening is greatly reduced.
• the rigidity at the groove opening portion of the sipe 20 is large. Since the index F is set to be larger than the stiffness index F at the end of the block, the decrease in block rigidity near the opening is kept while the sipe depth is kept constant, and the block rigidity is made uniform in the sipe longitudinal direction. It becomes possible.
• the pattern of the sipe 20 is bilaterally symmetric with respect to the tire equatorial plane CL, so there is no directionality when the vehicle is mounted.
• the sipe pattern is symmetric with respect to the tire equatorial plane CL. Therefore, the deformation of the block 18 during cornering is suppressed regardless of the orientation of the pneumatic tire 10. be able to.
• sipe amplitude ⁇ 3 on the main groove opening side may be set larger than the sipe amplitude ⁇ 3 ′ on the terminal end side in the block.
• the main groove opening side of the sipe 20 is entirely outside the vehicle (the arrow OUT direction side.
• the arrow IN direction represents the inside direction when the vehicle is mounted. )
• the direction of the sipe 20 and the mounting direction to the vehicle are specified.
• the rigidity index on the outside of the vehicle that is, on the side of the lateral force input is increased in the sipes 20 of all the blocks 18, and the deformation of the block 18 during cornering is suppressed. Is preferred.
• the sipe 20 crosses the block 18 in the tire axial direction (arrow L direction and arrow R direction). Therefore, Sipe 20 If you do not cross, you can get a higher edge effect than in the case.
• the stiffness index F on both sides is preferably set larger than the stiffness index F on the center side.
• the sipe amplitudes ⁇ 1 and ⁇ 2 on both sides are set to be larger than the central sipe amplitudes ⁇ , and ⁇ 2.
• the sipe amplitude ⁇ 3 on both sides may be set larger than the central sipe amplitude ⁇ 3 '!
• Startability on snow The vehicle was started on snow and the time until the speed reached 25 kmZh was measured. The shorter the time, the better the performance.
• Level difference before and after sipe After running 8000 km on a test course consisting of a dry paved road at an average speed of 35 kmZh, the level difference before and after sipe (near the main groove opening) was measured. The smaller the level difference, the better the performance.
• FIG. 5 (A) shows a tread pattern force of Comparative Example 1.
• FIG. 5 (B) shows a cross-sectional view of the block of Comparative Example 1 along the sipe.
• FIG. 6A shows a tread pattern force of Comparative Example 2.
• FIG. 6B shows a cross-sectional view of the block of Comparative Example 2 along the sipe.
• FIG. 7A shows a tread pattern force of the embodiment.
• FIG. 7B shows a cross-sectional view along the sipe of the embodiment.
• the tire of Comparative Example 1 uses a sipe with a constant axial stiffness index F and depth!
• the axial stiffness index F is constant.
• a sipe having a shallow sipe depth at the opening to the circumferential main groove is used.
• the stiffness index F in the axial direction is different, and the stiffness index F of the opening to the circumferential main groove is greater than the stiffness index F of the terminal end portion in the block.
• the stiffness index F is constant in the sipe longitudinal direction, whereas in the embodiment, the stiffness index F on the opening side is set large.
• each test tire is 205Z60R15 91V.
• the tire of the example to which the present invention was applied was found to be capable of starting on snow and braking on snow. As a result, it has a high performance even after wear.
• the present invention can be applied to a vehicle having both uneven wear and wet and snow performance.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Tires In General (AREA)

Priority Applications (5)

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Publications (1)

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ID=35781874

Family Applications (1)

Country Status (9)

Cited By (5)

Families Citing this family (3)

Citations (6)

Family Cites Families (10)

• 2005
  • 2005-06-28 JP JP2006528703A patent/JP4589926B2/ja not_active Expired - Fee Related
  • 2005-06-28 CN CNB2005800216166A patent/CN100473548C/zh not_active Expired - Fee Related
  • 2005-06-28 RU RU2007102514/11A patent/RU2333842C1/ru not_active IP Right Cessation
  • 2005-06-28 WO PCT/JP2005/011822 patent/WO2006001446A1/ja active Application Filing
  • 2005-06-28 EP EP05765355A patent/EP1769946B1/en not_active Not-in-force
  • 2005-06-28 ES ES05765355T patent/ES2328600T3/es active Active
  • 2005-06-28 US US11/630,134 patent/US20120037288A1/en not_active Abandoned
  • 2005-06-28 DE DE602005016418T patent/DE602005016418D1/de active Active
• 2007
  • 2007-01-26 NO NO20070501A patent/NO330383B1/no not_active IP Right Cessation

Patent Citations (6)

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